Surgical Anatomy of Endoscopic Endonasal Surgery for Anterior Skull Base and Parasellar Lesion

Abstract

  The surgical procedures applied during the endoscopic endonasal approach for anterior skull base and parasellar lesions, which include transsphenoidal and transplanum transtuberculum approaches, can be divided into four phases : the nasal/paranasal sinus phase, skull base bone resection, tumor resection, and cranial base reconstruction. In the nasal and paranasal phases, the key anatomies are the olfactory mucosa, posterior branch of the sphenopalatine artery, palatovaginal canal, and vidian canal. In the skull base bone resection phase, the key anatomies are the optic canal, carotid prominence, posterior clinoid process, medial/lateral opticocarotid recess, tuberculum sellae, planum sphenoidale, and anterior intercavernous sinus. During tumor resection, the pituitary gland, cavernous sinus, diaphragma sellae, intradural structures, pituitary stalk, optic nerve, internal carotid artery, and superior hypophyseal artery are involved. In each surgical phase, these anatomical structures should be accurately confirmed, and normal structures should be preserved.